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Family:
Asteraceae
burragweed, more..., skeleton-leaf burr-ragweed, skeletonleaf burr ragweed, skeletonleaf bursage
[Franseria discolor Nutt., more, Franseria tomentosa (Nutt.) A. Nels., non A. Gray, Gaertneria discolor (Nutt.) Kuntze, Gaertneria tomentosa (Nutt.) Heller]
 Max Licher |
Perennials, 10-30+ cm. Stems erect. Leaves mostly alternate; petioles 8-25(-35+) mm; blades elliptic to lance-elliptic, 50-80(-180+) × 12-20(-50+) mm overall, (1-)2(-3)-pinnately lobed (lobes ± deltate), bases cuneate, ultimate margins with ± deltate teeth, abaxial faces densely finely scabrellous (silvery gray), adaxial faces strigillose. Pistillate heads clustered, proximal to staminates; florets (1-)2. Staminate heads: peduncles 2-9 mm; involucres saucer-shaped (with black nerves), 3-6+ mm diam., strigillose; florets 25-40+. Burs: bodies ± pyriform, somewhat flattened, 1.5-2.5(-4) mm, finely scabrellous, spines (1-)8-12+, scattered, stoutly conic, 0.5-1+ mm, tips straight. Flowering Jun-Sep. Seasonally wet clays or sands, disturbed sites; (200-)1200-2100 m; Ariz., Colo., Idaho, Ill., Iowa, Kans., Mo., Mont., Nebr., N.Mex., N.Dak., S.Dak., Tex., Utah, Wis., Wyo.
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